Knife drive for a reciprocating mower



Nov. 17, 1964 N. TOFFIN KNIFE DRIVE FOR A RECIPROCATING MOWER Filed June 14, 1962 IN VENTOR NICHOLAS TOFF! N a T TO FIVE) United States Patent 3,157,018 KNEFE DRIVE FOR A RECIPROCATING MOWER Nicholas Toflin, 856 Nottingham Ave, Winnipeg 15, Manitoba, Canada Filed June 14, 1962, Set. No. 202,448 1 Claim. (Cl. 56- 296) My invention relates to new and useful improvements in knife drives for agricultural implements.

The conventional way of operating the reciprocating cutting knives of agricultural implements such as swathers comprises a pitman or rocking arm pivoted to the frame, one end of the arm being engaged centrally with the knife and the other end being connected to the oscillating drive mechanism.

This method of driving suffers from several disadvantages, the principal one of which is the excessive vibration due to the rapid oscillation of the pitman.

Another disadvantage, following from the excessive vibration is excessive wear and general inefliciency of the operating mechanism.

I have overcome these disadvantages by providing a drive which operates between roller bearings and in which the connection to the knife moves parallel with the knife rather than with the swinging action of the pitman engagement, all of which cuts down vibration and wear and generally increases the efliciency of the operation.

The principal object and essence of my invention is therefore to provide a knife drive of the character herewithin described in which the principal portion thereof operates between roller bearings.

Another object of my invention is to provide a device of the character herewithin described in which the engaging portion of the drive to the knife operates parallel with the knife.

A yet further object of my invention is to provide a device of the character herewithin described which can readily be adapted for use with existiing cutting knife assemblies.

A yet further object of my invention is to provide a device of the character herewithin described which reduces wear of the knife mechanism.

A still further object of my invention is to provide a device of the character herewithin described which is simple in construction, economical in manufacture and otherwise well suited to the purpose for which it is designed.

With the foregoing objects in view, and such other objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawing in which:

FIGURE 1 is a top plan view of a portion of a cutting knife assembly showing my drive in situ.

FIGURE 2 is a cross-sectional view on a reduced scale, taken substantially in the plane of the line 22 in FIG- URE 1.

FIGURE 3 is a front view of the drive engaging the knife mechanism.

FIGURE 4 is a perspective enlarged view of the slide block per so.

In the drawings like characters of reference indicate corresponding parts in the different figures.

Proceeding therefore to describe my invention in de- 3,157,018 Patented Nov. 17, 1964 tail, reference character 10 shows the main support plate at the front of a swather or the like upon which the knife assembly collectively designated 11 is mounted.

The assembly includes a knife strip 12 upon which the triangular cutting knives 13 are mounted by means of rivets or bolts 14 in the conventional manner. This knife strip reciprocates on the support plate 10 and is mounted in the conventional manner.

Upon the support plate 10 I have secured a mounting plate 14 which is adapted to support for rotation, in a horizontal plane, a plurality of roller bearings 15 mounted upon pins 16.

It will be observed that there are four such bearings in spaced apart and parallel relationship between which is journalled for reciprocating motion, a slide block 17.

This slide block is grooved on the two side edges 18 as at 19 and'portions of the roller bearings 16 engage within these grooves so that the slide block 17 can reciprocate in the direcion of the double headed arrow 20 yet not become displaced from the roller bearings.

Centrally of the slide block I provide a knife driving member 22 welded thereto as at 22 and extending at right angles from the slide block to terminate in a reduced portion 23 adapted to engage with a clip or retainer 24 secured to the aforementioned knife strip 12 by means of bolts 21.

This end 23 is maintained centrally within the clip by means of small blocks 25 upon each side thereof held by bolts 21', thus eliminating side play and transmitting the reciprocating movement to the knife assembly 11.

Secured to one end 26 of the slide block 17 is an actuating arm 27 and a drive arm 28 is pivotally connected by one end thereof to the end of the actuator arm 27 by means of the roller bearing connection 29.

The opposite end 30 of the arm 28 engages an eccentric crank pin 31 upon a drive wheel 32 also by means of a roller bearing 31', which drive wheel may be rotated by means of belt 33 from the source of power (not illustrated).

In operation, the rotation of drive wheel 32 causes the arm 28 to reciprocate the slide block 17 in the direction of the double headed arrow 20 between the roller bearings 15 thus operating the knife assembly 11 in the same direction without vibration or undue wear occurring.

Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the claim without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.

What I claim as my invention is:

In a swather knife assembly, the combination of a horizontally elongated support plate having a front edge portion, a knife reciprocable on said front edge portion of said support plate, a horizontal mounting plate secured to said support plate rearwardly of said knife, front and rear pairs of mutually spaced upstanding pins provided on said mounting plate, front and rear pairs of anti-friction bearings mounted for rotation in a common horizontal plane on the respective front and rear pairs of pins, a slide block reciprocable on said mounting plate between said bearings in a direction parallel to the reciprocating movement of said knife, said slide block having front and rear edges provided with grooves having peripheral edge 3 portions of the respective front and rear pairs of bearings disposed therein whereby to guide the reciprocating movement of the slide block, a finger-like drive member rigidly secured to said slide block and projecting forwardly therefrom, a retainer secured to said knife and having the front end portion of said drive member in engagement therewith whereby said knife may be reciprocated by reciprocating movement of the slide block, a drive Wheel rotatable in a horizontal plane adjacent said support plate, a crank pin provided on said drive wheel, a horizontal arm pivoted at one end thereof on said crank pin and pivotally connected at its other end to said slide block whereby to impart reciprocation to the slide block by ro- References Eited in the file of this patent UNITED STATES PATENTS 609,709 Shonle Aug. 23, 1898 2,114,436 Willis Apr. 19, 1938 2,500,818 Grate Mar. 14, 1950 2,867,070 icCall et a1 Jan. 6, 1959 FOREIGN PATENTS 1,017,400 Germany Oct. 10, 1957 

